I need to implement a sort-of failover-loadbalancing where systems
would receive gateway address from at least two routers (including
metric preference if possible). This needs to be done so that no special additional config is required on routers for each new system and for
each system all they need is gateway address and nothing else (no routes will be advertised to the router; but for security I'll want to specify
that no routes should be accepted). The systems receiving the routes
would be primarily linux PCs but will also include several windows and solaris machines. I don't want to use RIP (any version) or proxy ARP.
The routers are currently all cisco equipment.
Any suggestion as to what IGP protocol is best for this scenario?
This is more of a cisco-nsp question, but probably OSPF, as it's supported by the routing daemons on most *NIXes out of the box. I don't know about Windows.
Are you doing anycasting or something?
If simple redundancy in the default gateway is the goal, another (and probably simpler) method is to implement HSRP or GLBP between your routers which are serving the hosts in question.
I need to implement a sort-of failover-loadbalancing where systems
would receive gateway address from at least two routers (including
<snip>
Any suggestion as to what IGP protocol is best for this scenario?
ipv6 and RA ? oh wait, no widescale deployment of ipv6 
Paul, or someone
from ISC, has mentioned using ospf for this in the past.
Are you sure you need an IGP at all? Is it possible
that HSRP or GLBP could fit your needs?
-David
David Barak
Need Geek Rock? Try The Franchise:
http://www.listentothefranchise.com
Any suggestion as to what IGP protocol is best for this scenario?
This is more of a cisco-nsp question, but probably OSPF, as it's supported
by the routing daemons on most *NIXes out of the box. I don't know about Windows.
If this was 5+ years ago, I'd have said RIP as it works great for supplying only gateway address, but I want RIP to go RIP and will
not use it again. So yes OSPF seems like best choice, but I was
hoping something simple for gateway-only is available. I've no idea
yet how to deal with Windows (all win2000 and win2003), anybody?
Are you doing anycasting or something?
Yes, anycasting will be involved but only for very small number of
servers (all linux) - that is kind-of separate issue. The equipment
itself however will only see local gateway addresses (obviously), so
it should not care or know about it.
If simple redundancy in the default gateway is the goal, another (and probably simpler) method is to implement HSRP or GLBP between your routers which are serving the hosts in question.
Can't use HSRP in this case (or IVRP or whatever else its called with non-cisco options) - too long to explain why.
From the sounds of what you are trying to accomplish, I'd think VRRP/HSRP would be more up your alley than any dynamic routing protocol. Also look at NIC teaming.
Best Regards,
-Michael
From: "william(at)elan.net" <william@elan.net>
To: Roland Dobbins <rdobbins@cisco.com>
CC: nanog@nanog.org
Subject: Re: Q on what IGP routing protocol to use for supplying only gateway address
Date: Thu, 14 Sep 2006 10:55:28 -0700 (PDT)
Any suggestion as to what IGP protocol is best for this scenario?
This is more of a cisco-nsp question, but probably OSPF, as it's supported
by the routing daemons on most *NIXes out of the box. I don't know about Windows.
If this was 5+ years ago, I'd have said RIP as it works great for supplying only gateway address, but I want RIP to go RIP and will
not use it again. So yes OSPF seems like best choice, but I was
hoping something simple for gateway-only is available. I've no idea
yet how to deal with Windows (all win2000 and win2003), anybody?
At least a few years ago, Windows OSPF was a port of Bay RS, which was really Wellfleet code. So far, whenever I've needed to look at Windows and figure out how it did something, knowing RS usually gave me the answer.
Are you doing anycasting or something?
Yes, anycasting will be involved but only for very small number of
servers (all linux) - that is kind-of separate issue. The equipment
itself however will only see local gateway addresses (obviously), so
it should not care or know about it.
If simple redundancy in the default gateway is the goal, another (and probably simpler) method is to implement HSRP or GLBP between your routers which are serving the hosts in question.
Can't use HSRP in this case (or IVRP or whatever else its called with non-cisco options) - too long to explain why.
VRRP for the non-Cisco. I've recently had to deal with some situations, in VoIP, where the critical Call Agents have to stay in communication even if physically distant. 802.1w seves nicely to share a subnet between two geographically separate sites. Admittedly, one can reasonably count on dual OC-192s, diversely routed, and each connected to two switches at either end.
If you wanted it to load balance also I would use GLBP, if you didn't want to have to configure the clients with a gateway I would look into IRDP with GLBP.
william(at)elan.net wrote:
Hi,
In Answer to you question re Windows 2000/2k3 you would just need to install
routing and remote access service (RRAS) - part of windows, you can then add
OSPF as a routing protocol and tell it which adapter to listen on.
I have used this successfully when setting ISA Server up with a default
gateway off one nic (pointing towards the net - protected by a decent
firewall) and another pointing at the local network, one can then learn the
LAN routes using OSPF or RIP etc. and have a default route out the other
NIC.
Mark Kaye
william(at)elan.net